This application claims priority of International Application No. PCT/EP01/07768, filed Jul. 6, 2001 and German Application No. 100 32 395.2, filed Jul. 6, 2000, the complete disclosures of which are hereby incorporated by reference.
a) Field of the Invention
Nosepieces or slides, for example, for holding different objectives that are swung into or slid into the beam path, are coded in their individual positions, i.e., every position has a readable code. The coding can be carried out by means of micro-feelers or, optically, by means of reflection couplers or, magnetically, by means of Hall sensors.
b) Description of the Related Art and Recognition of Prior Art Shortcomings
When using Hall sensors, for example, every position is assigned a binary-coded quantity of magnets in a row which uniquely describe the position.
In every scanning position, these magnets are located across from the Hall sensors and can be detected. With exchangeable nosepiece units, e.g., motor-driven objective nosepieces (MOR) or manual objective nosepieces, there are different nosepieces with, e.g., 4, 5, 6 positions. Formerly, detection by the microprocessor was achieved via additional lines characterizing the quantity of maximum positions, or a value for the quantity of maximum positions was stored in the microprocessor.
When the nosepiece with 5 positions is replaced by a nosepiece with 6 positions, depending on the construction of the microscope, the internal control unit must recognize what type is installed so that it can be reported to the software and display. The disadvantage in known constructions consists in the additional wiring from the nosepiece, through the stand wiring, to the control electronics and the interrogation of the latter through corresponding port pins of the microprocessor.
The nosepiece type is permanently entered in the program without additional cable. However, modification would result in a change in the firmware.
Moreover, when the nosepiece type is stored in the microprocessor as a parameter, a suitable input device is required in every case (e.g., PCxe2x86x92download). Another possibility consists in keys or buttons on the microscope. This requires a display for checking the input.
In order to overcome these disadvantages, according to the invention, only the existing position coding is required.